Per the Robert James Peck of Newmarket tree at ancestry.com:
Kentish Gazette (Canterbury, Kent, England) - Marriage notice published 23 April 1850.
Also In the Chelmsford Chronicle (Chelmsford, Essex, England) - "...of Kingsnorth, John Hammond, Esq. of Ashley-hall, Cambridgeshire, to Emily, fifth daughter of the late Robert James Peck, Esq. of Newmarket Suffolk."